Improvement in machines for dressing milestones



.To all whom 'it may concern:`

Be it known that I, JOHN B. HARnIs, of the city of Ottawa, in the county of La Salle, and State of ures..

l liltittd tabe.

@aan can.

`JOHN n. HARRIS,'o-ror'rnwA, ILLINois.

Letters Patent No. 94,956,'date l-September 21, 1869.

IMPROVEMENT Al/[ACHIN'ES FCR, DRESSING VMI-lLST()NEKS.

".lhe Schedule referred to in these Letters Patent and making part of the same Illinois, have Iinvented a certain new and improved Millstone-Dresser; and I do hereby declare that the following is a full, clear, and exact description thereof, reference being had to theY accompanying drawings, making a part of 4this specilication, in which- -Figure l representsa `top or `plan view; Figure 2, an end view;. l

Figure 3, a front view of the vibrating arm; Figure 4, a side view; and Figure 5, a cross-section eccentric shaft. Like 'letters refer to same parts in all of the iig- 'llie 4nature of my invention.` consists in construct-' ing a millstone-dressng"machine, so that. it will have a rapid and accurate action, andfbe -under the complete control of the operator, by means of an adjustable or sliding'vibrating arm, to which the chisekoi pick is attached; in connecting such arm with a movable frame; in a novel device for changing the movableframe, and for operating the arm; and in the several parts and combinations hereinafter set forth and claimed as new.

` To enable others skilled in the art to make and use my machine, I will proceed to describe its construction andoperation.

The frame A is made of wood, or other suitable ma? inches high.

At theback end of tliisframe, I ,place a horizontal roller or shaft, K, by suitable bearings, as shown in g. 1.

This shaftor roller is pro'vided with a spiral groove or slot, b, and a longitudinal one, c,.connecting the v endsof b.

0n the outer end of this shaft K, I attach aratchet-i wheel, L, by means of which, with the `pawl N and lever M, the shaft is made to rotate.

Under the lever M, I' place an adjustable step vor rest f, which is adjusted bythe set-screwg, so-that the pawl N will engage `each' tooth or notch of the ratchet-wheel, or each` second or third one, as may be desired.

The lever and pawl are returned lby means of the spring d, or by their own weight, or other suitable device. f v The lever M is pivoted at h, as shown at fig. 2, and,

when the wheel is to be moved, is depressed by the hand or foot, as maybe most convenient.

0n the top of frame A, I place an additional frame, B, O,and D, which is connected `with the lower frame -by tongues and grooves, as shown at iig.`2, or by any'other suitable means, and is designed to he moved forward and backward upon such lower flame.

The cross-bar C is .grooved on the top, as showny and'at the side near the end of this cross-bar, the

extends back to the shaft K, and has at its rear end a projecti'oma, which fits into'thegroove b, as shown at iig. 1. i

The shaft Q is attached to this supplementary frame by suitable -journal.-bearings, and is Ymade oval or eccentric, as shown at fig. 5, or of any other form that will give motion to the arm.

I then make an arm, E, which is not attached to the frame, but may be taken oit' at any time. At the back end of this arm, I `attach ashort cross-bar, e, which is rounded oif at the bottom, and rests in the groove ofthe' cross-bar O, as shown. lAt the other end,\it is carried down by a pendent bar, F. At the 'lower end of this bar there is a collar, H, through which the pick orchisel I passes, which pick is p'revented from sliding out, and is partially held in place, by a set or thumb-screw,j.

Ihe pick I is providedwith asuitable point, and is made of steel, suitably tempered.

Immediately above the pick, I place a sliding rest or adjustable stop, G, which is pressed against the upper end of the pick proper, and fastened by theA vs crew fi, which passes through a slot in the' rest. `terial, and is about sixteen inches square, and seven The har Fis made long enough to reach lvery near `the bottom of the frame A, and the pick-point adjusted to go far enough below that frame to form a groove or channel in the stone of thedesired depth, so as to make the channels or grooves of the stone even and uniform. f

In use, the dresser is placed on the face o"f the stone to be dressed, and is held in place by placing the foot or knee upon tlle'extended end of A, or upon the Iaohine, as it is designed to be operated by hand; but, under favorable circumstances, other motive-power may be lused.

When placed in the-proper position, the operator grasps the handle on .wheel O with one hand, and places `the other onE'; the wheel O gives the oval or eccentric shaft Q a rapid motion, whichcauses the arm E to vibrate with great rapidity, and strikes the pick against the stone.` The arm is held in this position until the pick has penetrated the stone to the desired depth, when it is moved sideways, as indicated in red, and kept'in place andposition bythe cross-bare.

When the arm E has been passed across the machine,the lever M is depressed, which moves the shaft K, when the spiral groove b, acting upon the head a o1' the shaft or rod J advances the frame B the proper distance for a new groove in the stone, the distance for it to move having been adj usted by the step or rest f, under the lever M. The operation is then repeated, and continued until the spiral groove b has been traversed its entire length by the head a, when the frame B is returned to its original position, the Vhead a passing through the longitudinal-groove e. lhe machine is then moved to a new position, or the stone moved under it, ready for a fresh operation, and so on until the entire stone is dressed,

Having thus fully described my millstone-dresser,

What I claim as new, and desire to secure by Letters Patent, isv 1. rlhe arm E, in combination with eccentric or can1- shaft. Q, and guide-bar C, so that the arm may be moved from side to side, Without disturbing its vibrations, substantially as set forth.

2. The bar J, in combination with the grooved shaft K, for moving the frame B upon the base-frame, substantially as specified.

3. The shaft or roller K, when provided with the spiral groove b and the longitudinal groove c, substantially as and for the purposes described.

4. The adjustable stop or rest f, in combination with the lever M, pawl 1N, and ratchet-Wheel L, for adj ustiug the movement of the frame B, substantially as specified.

5. The adjustable stop G, provided with the setq screwgi, in combination with the pick I, provided with the set-screw j and the arm E F, for adjusting the exact distance for the pick to enter the stone, substantially as specified.

6. The combination `and,arrangement of the frames A and B, arms E F, sha Q, guide C, arm or rod J, and roller K, with lthe ratchet-wheel L and vdrivingmechanism, substantially as set forth.

' JOHN B. HARRIS. Witnesses: i

H. K.BOYL E, BIRD BICKFORD. 

